Design and Organocatalytic Asymmetric Synthesis of Indolyl-Pyrroloindoles Bearing Both Axial and Central Chirality.

An axially chiral indolyl-pyrroloindole scaffold, a new member of axially chiral indole-based scaffolds, has been designed, and the catalytic asymmetric construction of this scaffold has been established by the strategy of organocatalytic asymmetric (2 + 3) cycloaddition of 3,3'-bisindoles with isoindolinone-based propargylic alcohols. By this approach, a series of indolyl-pyrroloindole derivatives bearing both axial chirality and central chirality were synthesized in high yields with excellent diastereo- and enantioselectivities (up to 95% yield, 91:9 dr, 99% ee). This reaction not only realizes the first catalytic asymmetric (2 + n) cycloaddition of 3,3'-bisindoles as 1,2-dinucleophiles but also provides a new strategy for atroposelective construction of axially chiral indole-based scaffolds bearing five-five-membered rings, thus solving the challenges in constructing this class of axially chiral indole-based scaffolds.

Natural recovery from fire disturbance is more favorable than assisted recovery for the restoration of soil nematode-trapping fungi.

A fire is usually considered a severe disturbance factor in the environment. Globally, rising temperatures and increasing human activities have intensified the severity and frequency of fire incidents, and research on post-fire recovery has inevitably become an important focus for ecologists. In terms of the restoration of burned areas, there are usually two primary approaches: natural recovery and assisted recovery. However, very few relevant studies have systematically compared these recovery alternatives, suggesting which one is more favorable to the overall restoration of an ecosystem, especially to the soil microbes that function as indispensable components of ecosystems. In this study, the restoration of soil nematode-trapping fungi (NTF) in natural and assisted recovery environments was compared. The results showed that although the NTF community structures differed among the sample sites, the counts and diversity of the NTF communities in the upper and lower soil layers in the natural recovery area were higher than those in the assisted recovery and unburned control areas. These findings suggest that artificial efforts to help ecosystem recovery after fire negatively affect the speed and quality of soil NTF community recovery. Instead, natural recovery appears to be a more suitable land management choice after fire disturbance.

(4 + 2) cyclization of aza-o-quinone methides with azlactones: construction of biologically important dihydroquinolinone frameworks.

A base-promoted (4 + 2) cyclization of aza-o-quinone methides (aza-o-QMs) in situ generated from N-(o-chloromethyl)aryl amides was established. In this approach, azlactones were utilized as competent two-atom reaction partners to undergo (4 + 2) cyclization with aza-o-QMs, which afforded a series of dihydroquinolinone derivatives in overall good yields (up to 98%). This protocol has not only advanced the development of aza-o-QM-involved reactions, but also offered a useful method for constructing biologically important dihydroquinolinone frameworks.

Atroposelective Access to Oxindole-Based Axially Chiral Styrenes via the Strategy of Catalytic Kinetic Resolution.

Atroposelective synthesis of axially chiral molecules has attracted substantial attention from chemists because of the importance of such molecules. However, catalytic asymmetric synthesis of axially chiral styrenes or vinyl arenes is underdeveloped and challenging due to the low rotational barrier and weak configurational stability of such molecules. Therefore, the development of powerful strategies for the catalytic atroposelective synthesis of axially chiral styrenes or vinyl arenes is of great importance. In this work, we have accomplished the first atroposelective access to oxindole-based axially chiral styrenes by the strategy of catalytic kinetic resolution, and this strategy offered two kinds of oxindole-based axially chiral styrene derivatives in good diastereoselectivities (up to 94:6 dr) and excellent enantioselectivities (up to 98% ee) with high selectivity factors (S up to 106). This strategy not only provides easy access to oxindole-based axially chiral styrenes but also offers a robust method for synthesizing bisamide derivatives bearing both axial and central chirality. More importantly, this strategy has added a new class of members to the atropisomeric family, especially to the family of axially chiral styrenes.

Orange-spotted grouper (Epinephelus coioides) NADPH oxidase: Cloning and expression analysis after Cryptocaryon irritans infection.

Phagocytic cells are activated to produce a large amount of reactive oxygen species (ROS) that kill pathogens quickly and efficiently through oxidation. NADPH oxidase is the main source of intracellular ROS. In the present study, five subunits of the phagocytic NADPH oxidase complex were identified in orange-spotted grouper (Epinephelus coioides). The open reading frame of grouper gp91phox, p22phox, p67phox, p47phox, and p40phox were 1,698 bp, 564 bp, 1,497 bp, 1,290 bp, and 1,050 bp, respectively, and encoded 565, 187, 498, 429, and 349 amino acids. Evolutionary analysis indicated that these proteins are evolutionarily homologous to the corresponding proteins of other fish and mammals, and contain conserved functional domains and sites that are important in mammals. In addition, real-time polymerase chain reaction analysis showed that the expression of these five genes was higher in immune-related tissues in normal grouper, and that these genes were up-regulated in gill and spleen after C. irritans infection, which suggests that these genes may be involved in the defense against C. irritans infection.

Cooperative Catalysis-Enabled Asymmetric α-Arylation of Aldehydes Using 2-Indolylmethanols as Arylation Reagents.

A catalytic asymmetric α-arylation of aldehydes using 2-indolylmethanols as arylation reagents has been established. This reaction was enabled by a cooperative catalytic system consisting of a gold complex, a Brønsted acid, and a chiral amine, which have a synergistic effect in the reaction process. By using this strategy, a series of α-arylation products of aldehydes were generated in overall acceptable yields and good enantioselectivities (up to 69%, 91:9 er). The control experiments demonstrated that the addition of PPh3AuCl as a gold complex was helpful to improve the yield, and trifluoroacetic acid as a Brønsted acid played a crucial role in the reaction by promoting the generation of carbocation and chiral enamine intermediates, which are two key intermediates of the asymmetric α-arylation reaction. In addition, the enantioselectivity of the reaction was mainly controlled by the chiral amine catalyst via forming a chiral enamine intermediate. This reaction has not only provided a useful protocol for catalytic asymmetric α-arylation of aldehydes but also enriched the research contents of 2-indolylmethanol-involved reactions and asymmetric cooperative catalysis.

Identification and characterization of myeloperoxidase in orange-spotted grouper (Epinephelus coioides).

Cryptocaryon irritans is an important protozoan ciliate, which has led to heavy economic losses in marine aquaculture. Previous studies have indicated that C. irritans infection could induce the migration of neutrophils to infection sites. Myeloperoxidase (MPO) mainly exists in the cytoplasmic granules of the neutrophil and performs its function by a unique enzymatic capacity to produce hypohalous acid and other toxic oxidants. To determine the involvement of MPO and neutrophils against C. irritans infection in the host, we amplified MPO cDNA (EcMPO) from orange-spotted grouper (Epinephelus coioides). The open reading frame (ORF) of EcMPO encodes a putative polypeptide of 770 amino acids and has typical structural characteristics of mammalian MPO, including a signal peptide, a propeptide, a light chain, a heavy chain, and a peroxidase domain. Bioinformatics analysis has demonstrated that the most important functional sites in mammalian MPO were also conserved in grouper and other piscine MPO, implying the functional conservation of this protein during evolution. A rabbit anti-MPO recombinant protein polyclonal antibody was produced, which could recognize the native MPO protein. The expression of EcMPO was higher in the lympho-hematopoietic organs, such as head kidney, trunk kidney, spleen, but lower in muscle, heart, and brain. After infection with C. irritans, the EcMPO transcript was significantly up-regulated at specific time points in the infection sites (skin and gill) and systemic immune organs (head kidney and spleen); The number of EcMPO positive cells first increased and then decreased in the gill, but was still higher than the control after 7 days. These results demonstrated that EcMPO and its positive cells may be involved in anti-C. irritans infection in the grouper, which is attributed to the innate immune mechanisms of the host against parasite infection.

Direct C3-arylations of 2-indolylmethanols with tryptamines and tryptophols via an umpolung strategy.

A Brønsted acid-catalyzed direct C3-arylation of 2-indolylmethanols with tryptamines and tryptophols has been established, leading to a series of potentially bioactive 2,3'-biindole derivatives with a broad substrate scope and generally good yields (38 examples, up to 96% yield). In this process, the reactivity of the C3-position of 2-indolylmethanol is switched from nucleophilic to electrophilic, which can serve as an umpolung strategy in indole chemistry. This protocol not only provides a new strategy for accessing structurally diversified 2,3'-biindolyl frameworks, but also satisfies the requirement of green chemistry.

[Clinical Research on the Post-operative Hemodynamics Changes in Donors after Living Donor Liver Transplantation].

OBJECTIVE: To investigate the postoperative hemodynamics changes and their influence factors in the donors after right lobe living donor liver transplantation. METHODS: A total of 53 consecutive living donors from Dec 2010 to Aug 2015 who underwent donor right lobe hepatectomy were retrospectively analyzed. We measured residual liver hemodynamics with color doppler ultrasound, detected liver stiffness by transient elastography, also analyzed postoperative liver function, hemodynamics, and the long term variation tendency of hepatocirrhosis and spleen. RESULTS: One week after operation, transient liver damage was observed. Post-operative hemodynamics within the follow-up time showed:portal vein diameter was gradually increasing, the velocity decreased gradually;Hepatic vein diameter increased, and the velocity decreased gradually. There was a negative correlation between portal vein diameter and portal vein velocity (P=0.012, r=-3.11). Liver stiffness (Kpa value) decreased gradually with time, while spleen volume gradually increased. Correlation analysis showed that postoperative liver stiffness (Kpa value) was negatively related to portal vein diameter (P=0.013, r=-0.338) and positively related to hepatic venous velocity (P=0.038,r=0.246). CONCLUSIONS: The donor presented a transient liver injury after operation, but tended to be recovery after one week. Despite post-operative hemodynamic undergo a series of changes, but it does not affect the post-operative long-term donor safety.

Enantioselective Construction of Cyclopenta[b]indole Scaffolds via the Catalytic Asymmetric [3 + 2] Cycloaddition of 2-Indolylmethanols with p-Hydroxystyrenes.

The catalytic asymmetric [3 + 2] cycloaddition of 2-indolylmethanols to p-hydroxystyrenes was established in the presence of a chiral phosphoramide, and this reaction provided chiral cyclopenta[b]indole scaffolds in generally high yields and with good enantioselectivities (up to 98% yield, 99:1 er). The control experiments demonstrated that the dual hydrogen-bonding activation mode of the chiral catalyst toward the two substrates played an important role in the reaction. In addition, the large-scale reaction indicated that this catalytic asymmetric [3 + 2] cycloaddition could be scaled up for the synthesis of chiral cyclopenta[b]indole derivatives.

Identification and expression analysis of three XCR1-like receptors from Epinephelus coioides after Cryptocaryon irritans infection.

The unique receptor XCR1 of the XC subfamily of chemokines is specially expressed in CD8α-like dendritic cells. This receptor has one ligand in mice (XCL1) and two ligands in humans (XCL1 and XCL2). In mammals, the XCR1-XCL1 complex performs a vital role in regulating the localization and function of T cells, dendritic cells, and other cell types. In this study, three XCR1-like receptors (EcXCR1, EcXCR1L, and EcCCR12) were identified from a transcriptome database of orange-spotted grouper. The open reading frames (ORFs) of EcXCR1, EcXCR1L, and EcCCR12 predictably encode 337, 348, and 358 amino acids, respectively. All receptors are seven trans-membrane proteins, and contain conserved functional regions, and conserved sites, that are crucial for the role of chemokine receptors in mammals. Conserved features include four cysteine residues in the extracellular regions, a "DRY" motif in the second intracellular loop, and common characteristics at the N-terminus that are important for ligand interaction. In healthy grouper, EcXCR1, EcXCR1L, and EcCCR12 were broadly expressed in all the tissues tested. EcXCR1 was expressed at high levels in the liver, and EcXCR1L, and EcCCR12 in the thymus. After grouper infection with Cryptocaryon irritans, EcXCR1 and EcCCR12 were up-regulated in the skin and the spleen, and EcCCR12 in the skin, gill, and spleen. EcXCR1L expression changed only slightly. These results imply that EcXCR1 and EcCCR12 may be involved in host defense against parasite infection. A polyclonal antibody was produced against EcCCR12, and used to detect EcCCR12-positive cells in peripheral blood. These results will contribute considerably to elucidate the biological role of piscine XCR1-like receptors and their ligands system in the future.

Molecular cloning and expression analysis of CCL25 and its receptor CCR9s from Epinephelus coioides post Cryptocaryon irritans infection.

Among other functions, CCL25/CCR9 has an important role in regulating the trafficking of developing T cells in the thymus, and in homing memory T cells to the small intestine. The function of this chemokine-receptor complex is not well studied in fish. We identified a CCL25-like (EcCCL25, 108 aa) and two CCR9-like sequences (EcCCR9aa 373 aa; and EcCCR9b, 375 aa) from a transcriptome database of orange-spotted grouper (Epinephelus coioides). EcCCL25, EcCCR9a, and EcCCR9b shared conserved structural features with homologs from mammals and from other fish, and a consistent relationship with phylogenetic trees and sequence identities. In healthy grouper, EcCCL25, EcCCR9a, and EcCCR9b were highly expressed in the thymus, and the gills, were expressed at lower levels in the stomach, and had different expression levels in other tissues. After infection with Cryptocaryon irritans, EcCCL25 expression was up-regulated at early time points in the spleen and head kidney, and in the skin, and gills at later time points; EcCCR9a expression was increased in the gill, spleen, and head kidney. After infection with C. irritans, EcCCR9b expression was reduced in all tissues tested. These results suggested that grouper CCL25/CCR9a complex may be involved in host defense against C. irritans infection.

Characterization and expression analysis of grouper (Epinephelus coioides) co-stimulatory molecules CD83 and CD80/86 post Cryptocaryon irritans infection.

Co-stimulatory molecules (CD83, CD80 and CD86), belong to immunoglobulin superfamily, are type I membrane glycoprotein, which express on antigen presenting cells and provide the second signal for the activation of T lymphocytes. In the present study, we cloned the grouper's CD83 (675 bp) and CD80/86 (876 bp). Homology analysis showed that both EcCD83 and EcCD80/86 shares the highest amino acid similarity (51% and 47%) for the overall sequence with puffer fish (Takifugu rubripes). Some conserved features and important functional residues in mammalian CD83, CD80 and CD86 were also identified from these molecules of teleosts including grouper, suggesting the function of both molecules may be conserved among vertebrates. In transfected HEK293T cells, both molecules localized on the membrane surface. Tissue distribution analysis showed both EcCD83 and EcCD80/86 mRNAs were mainly expressed in immune organs, and EcCD80/86 was extremely higher expressed in mucosal immune tissues including skin and gill than systematic immune organs, which indicates these co-stimulatory molecules may prime T cell activation in local mucosal tissues. In Cryptocaryon irritans infected groupers, the expression level of EcCD83 and EcCD80/86 were both seen significant up-regulation in the skin at most tested time points.

Role of the postoperative cholesterol in early allograft dysfunction and survival after living donor liver transplantation.

BACKGROUND: Many studies have confirmed that serum total cholesterol (sTC) concentrations were associated with underlying liver damage and the synthesis capacity of liver. However, the role of postoperative sTC level on evaluating graft function and predicting survival of recipients who underwent liver transplantation has not been discussed. METHODS: Clinical data of 231 living donor liver transplantation recipients from May 2003 to January 2015 were retrospectively collected. Patients were stratified into the low sTC group (sTC <1.42 mmol/L, 57 recipients) and high sTC group (sTC =1.42 mmol/L, 174 recipients) according the sTC level on postoperative day 3 based on receiver-operating characteristic curve analysis. The clinical characteristics and postoperative short- and long-term outcomes were compared between the two groups. RESULTS: Recipients with sTC <1.42 mmol/L experienced more severe preoperative disease conditions, a higher incidence of postoperative early allograft dysfunction (38.6% vs 10.3%, P<0.001), 90-day mortality (28.1% vs 10.9%, P=0.002) and severe complications (29.8% vs 17.2%, P=0.041) compared to recipients with sTC =1.42 mmol/L. The multivariate analysis demonstrated that sTC <1.42 mmol/L had a 4.08-fold (95% CI: 1.83-9.11, P=0.001) and 2.72-fold (95% CI: 1.23-6.00, P=0.013) greater risk of developing allograft dysfunction and 90-day mortality, and patients with sTC <1.42 mmol/L had poorer overall recipient and graft survival rates at 1-, 3-, and 5-year than those with sTC =1.42 mmol/L (67%, 61% and 61% vs 83%, 71% and 69%, P=0.025; 65%, 59% and 59% vs 81%, 68% and 66%, P=0.026, respectively). Cox multivariate analysis showed that sTC <1.42 mmol/L was an independent predicting factor for total recipient survival (HR=2.043; 95% CI: 1.173-3.560; P=0.012) and graft survival (HR=1.905; 95% CI: 1.115-3.255; P=0.018). CONCLUSIONS: sTC <1.42 mmol/L on postoperative day 3 was an independent risk factor of postoperative early allograft dysfunction, 90-day mortality, recipient and graft survival, which can be used as a marker for predicting postoperative short- and long-term outcomes.

Major surfome and secretome profile of Streptococcus agalactiae from Nile tilapia (Oreochromis niloticus): Insight into vaccine development.

Streptococcus agalactiae is a major piscine pathogen that is responsible for huge economic losses to the aquaculture industry. Safe recombinant vaccines, based on a small number of antigenic proteins, are emerging as the most attractive, cost-effective solution against S. agalactiae. The proteins of S. agalactiae exposed to the environment, including surface proteins and secretory proteins, are important targets for the immune system and they are likely to be good vaccine candidates. To obtain a precise profile of its surface proteins, S. agalactiae strain THN0901, which was isolated from tilapia (Oreochromis niloticus), was treated with proteinase K to cleave surface-exposed proteins, which were identified by liquid chromatography-tandem spectrometry (LC-MS/MS). Forty surface-associated proteins were identified, including ten proteins containing cell wall-anchoring motifs, eight lipoproteins, eleven membrane proteins, seven secretory proteins, three cytoplasmic proteins, and one unknown protein. In addition, culture supernatant proteins of S. agalactiae were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and all of the Coomassie-stained bands were subsequently identified by LC-MS/MS. A total of twenty-six extracellular proteins were identified, including eleven secretory proteins, seven cell wall proteins, three membrane proteins, two cytoplasmic proteins and three unknown proteins. Of these, six highly expressed surface-associated and secretory proteins are putative to be vaccine candidate of piscine S. agalactiae. Moreover, immunogenic secreted protein, a highly expressed protein screened from the secretome in the present study, was demonstrated to induce high antibody titer in tilapia, and it conferred protection against S. agalactiae, as evidenced by the relative percent survival (RPS) 48.61± 8.45%. The data reported here narrow the scope of screening protective antigens, and provide guidance in the development of a novel vaccine against piscine S. agalactiae.

Grouper (Epinephelus coioides) BCR signaling pathway was involved in response against Cryptocaryon irritans infection.

B cell antigen receptor (BCR) plays a crucial role in B cell development and antibody production. It comprises membrane immunoglobulin non-covalently associated with CD79a/CD79b heterodimer. After B cell activation, initial extracellular signals are transduced by BCR complex and amplified by two protein tyrosine kinases, LYN and SYK, which then trigger various pathways. In the present study, we cloned grouper genes for BCR accessory molecules, EcCD79a (669 bp) and EcCD79b (639 bp), as well as two protein tyrosine kinases, EcLYN (1482 bp) and EcSYK (1854 bp). Homology analysis showed that all four molecules had a relatively high amino acid identity compared with those in other animals. Among them, they all shared the highest identity with Takifugu rubripes (EcCD79a 49%, EcCD79b 52%, EcLYN 82% and EcSYK 77%). The conserved features and important functional residues were analyzed. Together with IgM and IgT, tissue distribution analysis showed that all six molecules were mainly expressed in immune organs, particularly systematic immune organs. In groupers infected with Cryptocaryon irritans, up-regulation of EcCD79a and b, EcIgM and EcIgT were not seen in the early stage skin and gill until 14-21 days. Up-regulation of EcCD79a was seen in head kidney at most time points, while EcCD79a and b were only significantly up-regulated in day 14 spleen. Significant up-regulation of EcIgT were seen in day 21 head kidney and day 1, day14 spleen. Significant up-regulation of EcIgM were seen in day 1 head kidney and 12 h spleen. In addition, two protein kinase genes, EcLYN and EcSYK, were up-regulated in the skin at most time points, which suggested that B cells may be activated at the skin local infection site.

Development and validation of a predictive score for perioperative transfusion in patients with hepatocellular carcinoma undergoing liver resection.

BACKGROUND: Liver resection is a major surgery requiring perioperative blood transfusion. Predicting the need for blood transfusion for patients undergoing liver resection is of great importance. The present study aimed to develop and validate a model for predicting transfusion requirement in HBV-related hepatocellular carcinoma patients undergoing liver resection. METHODS: A total of 1543 consecutive liver resections were included in the study. Randomly selected sample set of 1080 cases (70% of the study cohort) were used to develop a predictive score for transfusion requirement and the remaining 30% (n=463) was used to validate the score. Based on the preoperative and predictable intraoperative parameters, logistic regression was used to identify risk factors and to create an integer score for the prediction of transfusion requirement. RESULTS: Extrahepatic procedure, major liver resection, hemoglobin level and platelets count were identified as independent predictors for transfusion requirement by logistic regression analysis. A score system integrating these 4 factors was stratified into three groups which could predict the risk of transfusion, with a rate of 11.4%, 24.7% and 57.4% for low, moderate and high risk, respectively. The prediction model appeared accurate with good discriminatory abilities, generating an area under the receiver operating characteristic curve of 0.736 in the development set and 0.709 in the validation set. CONCLUSIONS: We have developed and validated an integer-based risk score to predict perioperative transfusion for patients undergoing liver resection in a high-volume surgical center. This score allows identifying patients at a high risk and may alter transfusion practices.

Efficacy and safety of transarterial chemoembolization combining sorafenib with or without immune checkpoint inhibitors in previously treated patients with advanced hepatocellular carcinoma: A propensity score matching analysis.

Purpose: To compare the efficacy and safety of transarterial chemoembolization (TACE) plus sorafenib and immune checkpoint inhibitors (T+S+ICIs) and TACE plus sorafenib (T+S) when treating patients with advanced hepatocellular carcinoma (HCC) who have previously received locoregional treatment. Materials and methods: A retrospective analysis was performed on the patients with Barcelona Clinic Liver Cancer (BCLC) stage C HCC from May 2019 to December 2020. These patients were treated with locoregional therapy and showed radiographic progression after the treatment. Patients received either T+S+ICIs or T+S. The outcomes, including disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety, were compared. The propensity score matching (PSM) methodology was used to reduce the influence of confounding factors on the outcomes. Results: Forty-three patients were included in the T+S group and 33 in the T+S+ICI group. After PSM (n = 29 in each group), patients who received T+S+ICIs had a higher DCR (82.8% vs. 58.6%, p = 0.043), longer median PFS (6.9 vs. 3.8 months, p = 0.003), and longer median OS (12.3 vs. 6.3 months, p = 0.008) than those who underwent T+S. Eastern Cooperative Oncology Group performance status was an independent predictor of PFS, and age was an independent predictor of OS. The incidence of treatment-related adverse events in T+S+ICIs was well controlled. Conclusions: Compared with TACE combined with sorafenib, TACE combined with sorafenib plus ICIs is a potentially safe and effective treatment regimen for patients with advanced HCC who previously received locoregional treatment.

[Research on identification of cucumber, stem and leaf based on spectrum analysis technology].

To be able to quickly identify the cucumber real time, the present paper studied the near infrared reflectance characteristics of cucumber, stem and leaf. Spectral reflectance of 138 samples (46 cucumbers, 46 stems and 46 leaves) was collected using near infrared spectroscopy in the band range of 600-1 099 nm indoor. After Savitzky-Golay smoothing preprocessing, random 108 spectral samples were put forward as calibration set. The weighted deviation method was used for choosing the spectral bands 690-950 nm that include much more information. The samples were analyzed by PCA method to extract the principal component scores, combining the Mahalanobis distance method the recognition model was established, and seven abnormal samples were excluded. The partial least squares (PLS) model was established by remaining 101 samples spectra of calibration set, which was used for predicting the validation set (30 samples except of the calibration set). The result shows that the correlation of the predicted value and the actual value reaches up to 0.994 1, and the correct recognition rate is 100%. This significantly illustrates that the near infrared spectral reflectance characteristics are different among the cucumbers, stems and leaves, which can be successfully applied to recognition of cucumber by the method. The developed technique can provide a new method for cucumber identification.